New 5-Megawatt Battery Storage Project At RMLD Will Further Reduce Peak Loads & Save Costs

Below is a press release from the Reading Municipal Light Department:

READING, MA — Reading Municipal Light Department’s (RMLD’s) Citizens’ Advisory Board (CAB) and Board of Commissioners (Board) unanimously approved the RMLD to enter into a purchase power energy agreement with Kearsarge Energy for a battery storage system in Wilmington that will be capable of discharging 5-megawatts over two hours.

The system will be used to reduce costs related to peak demand and is projected to average $200,000 in annual savings for the RMLD during the 20-year project lifetime.  The system is expected to be installed in 2023. The battery project will be collocated with the existing 2.1 megawatt RMLD Community Solar array that is also owned and operated by Kearsage Energy.

This project adds to RMLD’s existing battery storage capability, our Minuteman system, also a 5-megawatt, 2 hours system located in North Reading. RMLD plans to add a total 30-megawatts/90 megawatt-hours of battery storage to RMLD’s service area over the next three years to further reduce costs and increase the resiliency of our distribution network.

The battery will typically be dispatched over 2 hours, discharging a total of 10 megawatt hours, to cover critical peak transmission and peak capacity hours. Peaks occur when the highest level of electricity is consumed in our region, one annual capacity peak hour and 12 transmission peak hours (1 peak hour per month).  Peak electricity is expensive, affecting power supply costs; lower peaks equate to reduced costs. Reducing peaks can also reduce the grid’s use of less efficient and less environmentally friendly generators. To learn more about peak demand, visit

About Reading Municipal Light Department

Established in 1894, Reading Municipal Light Department (RMLD) is a municipal electric utility serving over 70,000 residents in the towns of Reading, North Reading, Wilmington, and Lynnfield Center. RMLD has over 30,000 meter connections within its service territory.

Like Wilmington Apple on Facebook. Follow Wilmington Apple on Twitter. Follow Wilmington Apple on Instagram. Subscribe to Wilmington Apple’s daily email newsletter HERE. Got a comment, question, photo, press release, or news tip? Email

Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s